Many in the folding kayak community believe folding kayaks and other skin-on-frame kayaks offer features that aid paddling efficiency. In a hardshell kayak, waves and chop on the water can slow down the momentum of the craft and push the kayak back. Some hypothesize flexible skin on such kayaks help the kayak absorb the energy of waves and current, which allows the boat to move more easily through rough conditions. Some paddlers find skin-on-frame kayaks to be very efficient paddling rougher waters, while many simply enjoy the feeling of closer contact with the water and waves.
The second group encompasses a range of modifications from upgrading the car's traction to replacing the engine, leaving only the body over a modern, powerful car (for example, the Sascha Fiss Volkswagen Lupo GTI).  Another modification combine a Trabant boday with a Japanese superbike engine, such as the Suzuki Hayabusa (a combination known as Trabusa). Some of these cars have a rated power of over 150 hp (112 kW). The Trabant's light weight gives a power-to-weight ratio of 11 lb/hp (149 W/kg), giving the vehicles a performance comparable to modern mid-range sports cars .